Hi - I was really surprised to see your post - well, I should say, I was surprised to discover a similar post-operative development in the arm pain you described. I had lumbar surgery (L2 to the pelvis) in 2021 and then 2 surgeries for hip replacement after I fell - all of this took place over 4 months' time. When I started P.T in a clinic - probably 8 weeks after the last surgery, I began to have the kind of pain you describe between the shoulder and elbow, but on the right side (right hip was replaced). At first it was treated with kinesthetic tape and some kinesthetic therapy; that went on for several months. The strange thing was, sometime I could raise my arm quite high with no pain; other times, anything and everything seemed to "set it off". I would describe it as muscle pain, not joint pain. My therapist suggested that I give it as much rest as possible, which I did, and now, two years and four months after the last surgery, it seems to be back to normal (no pain!). Whether this odd development was a "normal" reaction to surgery or not, I don't know. No one ever suggested that and I guess I did not think to ask. The whole pain experience is a mystery to me. I do take Gabapentin and Tramadol every 8 hours for peripheral neuropathy pain in the feet and hands - also seemingly a result or residual effect of the surgeries. I'm 76 and a widow and otherwise in good enough health to maintain my home by myself and my dog 😊(yay!). Prayers for you on your recuperation journey. 🙏